• 천문학회보
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• 제38권1호
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• pp.60.2-60.2
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• 2013

We investigate several eruptive hot plasma observations by Hinode/XRT. Their corresponding EUV and/or white light CME features are visible in some events. Using those observations, we determine the mass constraints of eruptive plasma by assuming simplified geometrical structures of the plasma. In some events, their associated prominence eruptions and eruptive plasma were observed in EUV observations as absorption or emission features. The absorption feature provides the lower limit to the cold mass while the emission feature provides the upper limit to the mass of observed eruptive plasma in X-ray and EUV passbands. We compare the mass constraints for each temperature responses and find that the mass in EUV and XRT are smaller in their upper or lower limit than total mass in coronagraph. About half eruptive events in XRT have no corresponding CME, which may be due to failed eruptions or low plasma density. In addition, some events were observed by a few passbands in X-ray, which allows the determination of the eruptive plasma temperature using a filter ratio method. We present the isothermal plasma temperatures by the filter ratio method. These are possibly an average temperature for higher temperature plasma because the XRT is more sensitive in higher temperature.

• Tuberculosis and Respiratory Diseases
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• 제44권3호
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• pp.493-504
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• 1997

연구배경 : 폐암은 예후가 나쁜 암중의 하나로 특히 비소세포암의 경우 화학요법이나 방사선요법에 반응이 적고 대부분 어려운 제III병기 이상에서 발견되기에 대한 예후를 증진시키기 위한 치료법의 개발에 관심이 집중되고 있다. 이와 관련하여 최근에 소량의 항암제를 투여하면서 방사선 치료를 병행하는 Concurrent chemoraditherapy가 소개되면서 효과나 부작용 면에서 Conventional radiotherapy보다 우수한 것으로 알려져 관심의 대상이 되고 있다. 연구방법 : 대상은 1994년 1월부터 1995년 8월까지 본원에서 비소세포성 폐암으로 진단된 환자중 병기가 제III병기 이상이며 수술이 불가능했던 29명과 제II병기이나 수술을 거부했던 환자 1명을 포함해 모두 30명을 대상으로 무작위로 15명씩 CCRT군과 XRT군으로 나누어 치료를 시행한 뒤에 각 치료 군간의 치료 반응, 치료에 따른 performance status의 변화, 부작용 발현 빈도 및 방사선 유도성 폐렴 발생 빈도 등을 비교하는 한편, 전체 환자들을 대상으로 치료 반응과 각 임상적 지표들간의 상관 관계를 관찰해 보았다. 결 과 : 치료 반응 접수나 순응도 점수에서는 두군간에 의미있는 차이를 보이지 않았으나, 부작용 면에서는 검사실 부작용 점수 및 방사선 유도성 폐렴 점수가 각각 CCRT 군이 XRT군에 비해 의미 있는 감소를 보였다(p < 0.05). 전체 환자에서 병기와 치료 반응 점수 사이에는 의미 있는 역상관관계가 있었으나(R=0.353. p < 0.05) 다른 평가 항목들은 치료 반웅과 상관관계가 없었다. 전체 환자군에서는 편평상피세포암군 환자가 선암환자보다 치료 반응 점수가 다소 높은 경향을 보였으며, CCRT군과 XRT군내에서는 CCRT군에서 편평상피세포암군이 치료 반응 접수가 높은 경향이 있었다. 또한 같은 세포 유형에서 두 군간에 치료 반응 점수를 비교해 본 결과 양군간에 차이가 없었다. 결 론 : 이상의 연구 결과 CCRT는 XRT에 비해 치료 반응이나 차이가 없으나, 부작용이 이점이 있는 것으로 사료되며 생존율에 대해서는 앞으로 추적 검사가 더 필요될 것으로 사료된다.

• 천문학회보
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• 제37권1호
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• pp.97-97
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• 2012

Hinode/XRT has observed coronal mass ejections (CMEs) since it launched on Sep. 2006. Observing programs of Hinode/XRT, called 'CME watch', perform several binned observations to obtain large FOV observations with long exposure time that allows the detection of faint CME plasmas in high temperatures. Using those observations, we determine the upper limit to the mass of hot CME plasma using emission measure by assuming the observed plasma structure. In some events, an associated prominence eruption and CME plasma were observed in EUV observations as absorption or emission features. The absorption feature provides the lower limit to the cold mass while the emission feature provides the upper limit to the mass of observed CME plasma in X-ray and EUV passbands. In addition, some events were observed by coronagraph observations (SOHO/LASCO, STEREO/COR1) that allow the determination of total CME mass. However, some events were not observed by the coronagraphs possibly because of low density of the CME plasma. We present the mass constraints of CME plasma and associated prominence as determined by emission and absorption in EUV and X-ray passbands, then compare this mass to the total CME mass as derived from coronagraphs.

• Computers and Concrete
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• 제32권6호
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• pp.607-613
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• 2023

The objective of this work is to determine the compressive strength of geopolymer concrete utilizing four distinct machine learning approaches. These techniques are known as gradient boosting machine (GBM), generalized linear model (GLM), extremely randomized trees (XRT), and deep learning (DL). Experimentation is performed to collect the data that is then utilized for training the models. Compressive strength is the response variable, whereas curing days, curing temperature, silica fume, and nanosilica concentration are the different input parameters that are taken into consideration. Several kinds of errors, including root mean square error (RMSE), coefficient of correlation (CC), variance account for (VAF), RMSE to observation's standard deviation ratio (RSR), and Nash-Sutcliffe effectiveness (NSE), were computed to determine the effectiveness of each algorithm. It was observed that, among all the models that were investigated, the GBM is the surrogate model that can predict the compressive strength of the geopolymer concrete with the highest degree of precision.

• Asian Pacific Journal of Cancer Prevention
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• 제14권11호
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• pp.6197-6208
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• 2013

Cancers will continue to be a threat to health unless they can be controlled by combinations of treatment modalities. In this review, evaluate the role of resveratrol (RSV) as a radiosensitizing agent was evaluated and underlying mechanisms holistically explored in different cancer models focusing on therapeutic possibilities. The ability of RSV to modify the effect of radiation exposure in normal and cancer cells has indeed been shown quite convincingly, the combination of RSV and IR exhibiting synergistic effects on different cancer cells. This is relevant since controlled exposure to IR is one of the most frequently applied treatments in cancer patients. However, radiotherapy (XRT) treatment regimes are very often not effective in clinical practice as observed in patients with glioma, prostate cancer (PCa), melanoma, for example, largely due to tumour radioresistant properties. Sensitization of IR-induced apoptosis by natural products such as RSV is likely to be relevant in cancer control and treatment. However, all cancers do not respond to RSV+IR in a similar manner. Therefore, for those such as the radioresistant PCa or melanoma cells, the RSV+IR regime has to be very carefully chosen in order to achieve effective and desirable outcomes with minimum toxicity to normal cells. They are reports that the highest concentration of 100 ${\mu}M$ RSV and highest dose of 5 Gy IR are sufficient to kill cells by induction of apoptosis, indicating that RSV is effective in radiosensitizing otherwise radioresistant cells. In general, it has been shown in different cancer cells that RSV+XRT effectively act by enhancing expression of anti-proliferative and pro-apoptotic molecules, and inhibiting pro-proliferative and anti-apoptotic molecules, leading to induction of apoptosis through various pathways, and cell death. If RSV+XRT can suppress the signature of cancer stemness, enhance the radiosensitivity by either targeting the mitochondrial functionality or modulating the tumour necrosis factor-mediated or Fas-FasL-mediated pathways of apoptosis in different cancers, particularly in vivo, its therapeutic use in the control of cancers holds promise in the near future.

• 천문학회보
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• 제36권2호
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• pp.89.1-89.1
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• 2011

We have investigated a coronal jet near the limb on 2010 June 27 by Hinode/X-Ray Telescope (XRT), EUV Imaging Spectrograph (EIS), Solar Optical Telescope (SOT), SDO/Atmospheric Imaging Assembly (AIA), and STEREO. From EUV (AIA and EIS) and soft X-ray (XRT) images we identify the erupting jet feature in cool and hot temperatures. It is noted that there was a small loop eruption in Ca II images of the SOT before the jet eruption. Using high temporal and multi wavelength AIA images, we found that the hot jet preceded its associated cool jet. The jet also shows helical-like structures during the rising period. According to the spectroscopic analysis, the jet structure changes from blue shift to red one with time, implying the helical structure of the jet. The STEREO observation, which enables us to observe this jet on the disk, shows that there was a dim loop associated with the jet. Comparing the observations from the AIA and STEREO, the dim loop corresponds to the jet structure which implies the heated loop. Considering that the structure of its associated active region seen in STEREO is similar to that in AIA observed 5 days before, we compared the jet morphology on the limb with the magnetic fields extrapolated from a HMI vector magnetogram observed on the disk. Interestingly, the comparison shows that the open field corresponds to the jet which is seen as the dim loop in STEREO. Our observations (XRT, SDO, SOT, and STEREO) are well consistent with the numerical simulation of the emerging flux reconnection model.

• 천문학회보
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• 제32권2호
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• pp.34.2-34.2
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• 2007

• 천문학회보
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• 제32권2호
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• pp.33.2-33.2
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• 2007

• 천문학회보
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• 제32권1호
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• pp.35.2-35.2
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• 2007

• 천문학회지
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• 제38권2호
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• pp.307-310
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• 2005

The Solar-B is the third Japanese spacecraft dedicated for solar physics to be launched in summer of 2006. The spacecraft carries a coordinated set of optical, EUV and X-ray instruments that will allow a systematic study of the interaction between the Sun's magnetic field and its high temperature, ionized atmosphere. The Solar Optical Telescope (SOT) consists of a 50cm aperture diffraction limited Gregorian telescope and a focal plane package, and provides quantitative measurements of full vector magnetic fields at the photosphere with spatial resolution of 0.2-0.3 arcsec in a condition free from terrestrial atmospheric seeing. The X-ray telescope (XRT) images the high temperature (0.5 to 10 MK) corona with improved spatial resolution of approximately 1 arcsec. The Extreme Ultraviolet Imaging Spectrometer (EIS) aims to determine velocity fields and other plasma parameters in the corona and the transition region. The Solar-B telescopes, as a whole, will enable us to explore the origins of the outer solar atmosphere, the corona, and the coupling between the fine magnetic structure at the photosphere and the dynamic processes occurring in the corona. The mission instruments (SOT/EIS/XRT) are joint effort of Japan (JAXA/NAO), the United States (NASA), and the United Kingdom (PPARC). An overview of the spacecraft and its mission instruments are presented.